Quadruple UV LED Array for Facile, Portable, and Online Intrinsic Fluorescent Imaging of Protein in a Whole Gel Electrophoresis Chip

Intrinsic fluorescence imaging (IFI) has been used for the stain-free detection of proteins in slab gel. However, complicated detection setups and small irradiation area limited the development of facile, online, and portable imaging of the whole slab gel. We here designed a quadruple UV LED array to produce even and powerful area light for direct irradiation of gel electrophoresis chip (GEC) at 275 nm. In addition, we only used a filter of 365 nm, a UV camera lens, and a CCD for IFI detection. We integrated the simple detection setup with the small GEC to construct the IFI-GEC device with a portable size of 15 x 15 x 38 cm. We detected three model proteins to demonstrate the good evenness of the LED array and the online imaging of the whole GEC. Furthermore, the reproducible IFI-GEC detection was completed within 10 min and the LOD was as low as 40 ng for lysozyme detection. All results indicated the potential of the IFI-GEC device for online and portable detection of proteins without staining.

Automated summary

In this study, a quadruple UV LED array was designed to directly irradiate gel electrophoresis chips at 275 nm. Simple detection setup using a 365 nm filter, UV camera lens, and CCD was integrated with the small gel electrophoresis chip to construct the IFI-GEC device. The LED array exhibited good evenness and enabled online imaging of the entire gel electrophoresis chip. The reproducible IFI-GEC detection was completed within 10 minutes with a low LOD of 40 ng for lysozyme detection, demonstrating the potential of the IFI-GEC device for stain-free online and portable protein detection.